isCOBOL Evolve : Appendices : Intrinsic Functions : HANDLE-TYPE
HANDLE-TYPE
The HANDLE-TYPE function returns the resource type pointed by a handle or zero if the handle is invalid.
Syntax 1
function handle-type (arg-1)
Syntax 2
$handle-type (arg-1)
Arguments
• arg-1 must be a USAGE HANDLE item.
Result
The function returns a number from 0 to 9. The isgui.def copybook includes constants that describe these values:
78  handle-is-invalid                            value 0.
78  handle-of-window                             value 1.
78  handle-of-subwindow                          value 2.
78  handle-of-font                               value 3.
78  handle-of-thread                             value 4.
78  handle-of-menu                               value 5.
78  handle-of-control                            value 6.
78  handle-of-bitmap                             value 7.
78  handle-is-unknown                            value 9.
Examples
Example - Test if a handle is invalid.
working-storage section.
77 my-handle usage handle.
...
procedure division.
...
if function handle-type(my-handle) = 0
display "my-handle points to nothing!"
end-if.